Bridged electrical plug

ABSTRACT

An electrical plug with power blades in a power bridge portion and a ground pin in a ground bridge portion, the portions being non-integrally joined.

FIELD OF THE INVENTION

This invention relates to electrical plugs, and more particularly tosuch plugs with a novel bride supporting and separating the power bladesfrom each other, and the ground prong from both.

BACKGROUND OF THE INVENTION

Plugs with two power blades and a ground prong are known in the priorart, as are use in the blades of folded and embossed (for thickeningwith use of less metal) strips of metal.

SUMMARY OF THE INVENTION

A new plug provides for not only easy and inexpensive automatedmanufacture, but good insulative qualities as well.

The new plug features an insulative bridge with a power blade bridgeportion carrying power blades, a ground bridge portion carrying a groundpin, and with internal means for cooperatively with ends of said powerblades anchoring them, the blades being further held in the bridge by acap closing blade-accepting slots in the bridge. Other features ofpreferred embodiments will be set forth in the following description andclaims.

PREFERRED EMBODIMENT

Following are drawings of a preferred embodiment, with descriptionthereof.

FIG. 1 is an isometric view of a subcombination of that embodiment.

FIG. 2 is a plan view thereof.

FIG. 3 is a sectional view taken at 3--3 of FIG. 1.

FIG. 4 is a side elevational view thereof.

FIG. 5 is a bottom view of said embodiment.

In FIG. 1 are shown a pair of folded conductive metal sheet strip bladesindicated generally at 10.

Each blade 10 has an outer layer 12 and an inner layer 14, each pairjoined respectively by a fold 16. Each outer layer 12 includes anoutwardly facing embossment 18 made by offsetting the corresponding areaof the opposing surface of that layer. Each inner layer 14 includes aninwardly facing embossment 20 made by offsetting the corresponding areaof the opposing surface of that layer. The effective thickness of eachblade 10 (as measurable with, for example, a micrometer caliper)measured through portions 18, 20 is thus more than twice the thicknessof the sheet metal of which blades 10 are formed.

All the layers 12, 14 extend into polypropylene power bridge elementindicated generally at 30. Element 30 includes a pair of slots 32extending in an element thickness direction and of a slot size foraccepting the double thickness of unembossed layers 12, 14, these slotsbeing open at ends 34. Slots 32 meet within element 30 transversely andlongitudinally extending blind slots 36, in which are accepted the bent90 degree ends of layers 14. Promontories 38 of element 30 define uppersurfaces of slots 36, while base 40 defines lower surfaces. Base 40includes on its outer surface farther away from blade folds 16 atransverse notch 42.

Open from the same transverse side of element 30 as slots 32 and 36 arethree blind orienting holes 50.

Lower slots 60 extend transversely and are blind from an open end on thesame side of element 30 as slot 32's transversely open end. Slots 60open into slots 32 and 36.

Secured to bridge element 30 is polypropylene cap 70, which includesorienting projections 72 seated in blind holes 50, and an inner surface74 which closes off slots 32, 36, and 60.

Outer layers 12 after extending through slots 60 of element 30 terminatein contact paddles 80, each of which is formed from the same metal stripas its respective portion 12 and is continuous therewith, and each ofwhich is rotated 90 degrees about an axis lying approximately along theinner surface of its layer 12 and parallel with the axis of symmetry ofpower bridge element 30.

Paddles 80 are bent inwardly of bridge element 30 toward each other,from layers 12, as best shown in FIG. 5.

Blind hole 90 in element 30 has seated therein mating projection 92integral with the ground bridge, indicated generally at 94.

Ground bridge 94 includes polypropylene support 96 carrying integralprojection 92 and ground pin 98 formed of a single sheet of conductivemetal, leaving opening 100 between adjoining sheet edges and slots 102in the upper hemispherical portion 104 of the formed pin 98. At itslower location 106 the there cylindrical pin 98 is cut along the line106, and (in FIG. 4) the left half-cylinder below line 106 removed, whatremains being flattened parallel to the plane going perpendicularly intothe paper to provide paddle 108, narrowed from 110 to its extremity.

The elements 70, 30, and 94 are fitted together and thermowelded into aunitary overall bridge assembly. The grooves 42 and 120 (the lattercorresponding in depth to the former, and in essence continuing it)provide for vibratory feeding in manufacture. The paddles 80 and 108 maybe crimped or welded for electrical connection.

The bent ends of layers 14 cooperate with slots 36 to provide excellentblade anchorage. Integral pins 72 cooperate with blind holes 50 toprovide excellent orientations, as do projection 92 and blind slot 90.

The polypropylene of elements 30, 94, 70 provide good insulativequalities.

The new plug also facilitates assembly of wires to the paddles.

Thermowelding of the ground bridge portion to the power bridge portionis preferably done after wires are attached to the appropriate paddles.

What is claimed is:
 1. An electrical plug comprising a plasticinsulative bridge,said bridge including a ground bridge portion and apower bridge portion, said ground bridge portion being secured to saidpower bridge portion non-integrally, and in which a single ground pin isheld on all sides thereof in said ground bridge portion, and a singlepair of power blades are each held on all sides thereof, respectively,in said power bridge portion.
 2. The plug of claim 1 in which said powerblades each consists of a formed and folded-on-itself strip ofconductive sheet metal.
 3. An electrical plug comprising a plasticinsulative bridge,said bridge including a ground bridge portion and apower bridge portion, said ground bridge portion being non-integrallysecured to said power bridge portion, said ground bridge portion holdingtherein a single ground pin, said power bridge portion holding therein asingle pair of power blades in which said power blades each consists ofa formed and folded-on-itself strip of conductive sheet metal, and inwhich a first layer of each said blade extends completely through firstslots in said power bridge portion and a second layer of each said bladeextends angularly away from said first layer inwardly of said powerblade, and is held in second slots of said power bridge portion soangularly related to said first slots.
 4. The plug of claim 3 in whichsaid first slots and said second slots are closed by an insulative capsecured to said power bridge portion.
 5. The plug of claim 4 in whichsaid ground bridge portion includes an integral elongated projection andsaid power bridge portion includes a mating blind hole.
 6. The plug ofclaim 4 in which one of said power bridge portion and said cap includesprojections and the other includes mating blind holes.
 7. The plug ofclaim 4 in which said power bridge portion includes a vibratory feederorientation groove.
 8. The plug of claim 4 in which each of said powerbridge portion and said cap are formed of plastic and secured together.9. The plug of claim 8 in which said plastic is polypropylene.
 10. Theplug of claim 8 in which said power bridge portion and said cap arethermoweldedly joined.
 11. The plug of claim 10 in which said powerbridge portion and said ground bridge portion are thermoweldedly joined..Iadd.
 12. An electrical plug comprising a plastic insulative powerbridge portion and a pair of power blades held therein,each of saidpower blades consisting of a formed and folded-on-itself strip ofconductive sheet metal, and in which a first layer of each said bladeextends completely through first slots in said power bridge portion anda second layer of each said blade extends angularly away from said firstlayer inwardly of said power blade, and is held in second slots of saidpower bridge portion so angularly related to said first slots, and inwhich each said first layer extends also completely through a third slotin said power bridge portion, said third slot being thinner than saidfirst slot, each said second slot communicating with each said firstslot inwardly of each said third slot. .Iaddend..Iadd.
 13. The plug ofclaim 12 in which said first slots and said second slots are closed byan insulative cap secured to said power bridge portion..Iaddend..Iadd.14. The plug of claim 13 in which one of said powerbridge portion and said cap includes projections and the other includesmating blind holes. .Iaddend..Iadd.15. The plug of claim 13 in whichsaid power bridge portion includes a vibratory feeder orientationgroove. .Iaddend..Iadd.16. The plug of claim 13 in which each of saidpower bridge portion and said cap are formed of plastic and securedtogether. .Iaddend..Iadd.17. The plug of claim 16 in which said plasticis polypropylene. .Iaddend..Iadd.18. The plug of claim 16 in which saidpower bridge portion and said cap are thermoweldedly joined. .Iaddend.